Transcript Bell Work
Bell Work: 12/3/14 •Quizlet Review –Number your bell work sheet 1-6 –On your bell work sheet, write down the words that match the definitions EQ & Objectives EQ •Can we research areas of health sciences— forensic science? Objectives TLW: •Identify different fingerprint classes. •Identify the unique ridge patterns of a fingerprint. •Develop latent prints from a crime scene and identify the fingerprint patterns. Latent Print Challenge Do the substances on people’s hands affect latent prints left on surfaces? Challenge: Your challenge is to design an experiment to see how substances on people’s hands, such as lotion, soap, and hand sanitizer, affect the quality of latent prints left on paper. Scientific Method: • (People) Purpose – State the problem • (Really) Research – Find out about the topic • (Hate) Hypothesis – Predict the outcome of the problem • (Eating) Experiment – Plan a procedure to test the hypothesis & test your hypothesis • (Dark) Data – Record the results of the experiment • (Chocolate) Conclusion – Compare the hypothesis to the experiment conclusion Complete the first three steps of the Scientific Method in your STEM notebook: 1. Write the purpose of the experiment (refer back to the latent print challenge page). 2. Complete research on the following topics: − Latent prints − Ninhydrin − Amino Acids − Amines • Answer the following question: What could be researched in order to find out what substances on human hands could react with Ninhydrin, developing a better quality print? • Decide what substances you want to use in your experiment. Think about common substances humans put on their hands. For example, you could use lotion. 3. Form a hypothesis: What substance on human hands will develop the best quality print? What you should have figured out from your research… 1. Latent prints are invisible prints that have to be developed by powders, special lights, or chemicals. 2. Ninhydrin is a chemical or solution that reacts with amines or amino acids from our skin (sweat and oils, which contain proteins) to turn the latent print purple. 3. We need to see what common substances that we put on our hands contain amines that could better react with the Ninhydrin to develop a better quality print. List of ingredients Hand Sanitizer Are any of these amines? Lotion Baby Powder IMPORTANT!!! You must meet the following standards tomorrow during the experiment: 1. You must wear closed toe shoes (NO sandals or flip flops!) 2. If you have long hair, you must have it pulled back! 3. You must wear pants or skirts that reach the ankle (NO capris, shorts, or mini-skirts!) and a long sleeve shirt. Tweet a response… What is your hypothesis? Predict which of your substances will have the greatest effect on the quality of latent prints.